Vibrational Spectra of Spodiosite Analogs

Spodiosite analogs are a class of compounds related to the apatite family. The ir spectra (4000 to 200 cm−1) and the laser-Raman spectra were obtained for several analogs (Ca2(XO4)Cl in which X=P, As, or V) prepared by a reaction flux technique. Fundamental modes were identified, and empirical band assignments were made. Unquestionable band assignment of the v2 modes can be made using Raman spectra. Effects of solid-state interactions were noted in the spectra and interpreted by factor-group analysis using the factor group D2h. The spectra of chlorspodiosite (Ca2(PO4)Cl) were compared with the spectra of synthetically prepared chlorapatite.